Settable magnesium cement (sorels cement) compositions are known, and such compositions containing sawdust filler are also known and have previously been used as settable flooring or floor-leveling compositions.
Such compositions generally comprise a mixture of magnesium oxide/magnesium chloride with sawdust or other suitable particulate filler. However, the quality and moisture content of the sawdust is of importance, otherwise the floor may break up, or become chalky and eventually crumble. The water content of the finely-comminuted sawdust component was required to be of less than 12%. It proved to be not easy to maintain this moisture percentage and it was found that higher moisture content gave rise to several problems such as the composition's not setting properly, the reaction not going to completion, and the like. Moreover, the presence of "free" magnesium chloride has been found to cause so-called "sweating". Also, the possibility of corrosion has undoubtedly existed when the composition came into contact with, say, steel or aluminium, usually in the form of door jambs or window sills, rusting steel and corroding aluminium.